基于土壤Bekker承压模型、Janosi剪切模型和塑性大变形原理分别建立着陆器足垫-月壤相互作用模型及铝蜂窝的力学模型,在此基础上应用ADAMS软件构建准确的着陆器整体的多体动力学模型,并结合力-角稳定性度量法,为着陆器安全软着陆提出了合理的稳定性判据.针对不同月面环境与着陆器着陆初始状态,通过数值计算模拟了着陆器在刚性或模拟月面上的软着陆冲击过程,着重分析了月面着陆环境和初始条件对软着陆稳定性的影响,并获得了着陆器发生倾覆时不同着陆偏航角与极限水平速度关系的稳定性边界曲线.同时,根据其边界稳定性曲线,找出了最恶劣工况,即偏航角为22.5°时的工况所容许的极限水平速度最小,工况最为恶劣.以上研究为着陆器实现软着陆月面环境和初始条件的选择或类似的工程设计提供指导方案.
Based on the Bekker soil pressure-bearing model,Janosi shear model and principles of plastic deformation,the interaction model of arch support of the lander and lunar soil and the aluminum honeycomb model were built separately,and on this basement a more accurate overall multibody dynamic model of lander was established by the ADAMS software.Combined with the measure method of force-angle stability,the authors have proposed a proper criterion for the safety of the soft landing stability for the lander.For the different circumstances of the moon surface and initial landing state of the lander,the authors have simulated the collision process of the soft landing on the rigid or simulative moon surface for the lander through numerical calculation.The impact of the landing circumstances and initial conditions on the stability of soft landing was specially analyzed,and the stability boundary curve of the relationship between different yaw angles and ultimate lateral speeds when the lander overturning is also obtained.Meanwhile,according to the stability boundary curve,the worst working case is found out,which happens when the yaw angle is 22.5° when the allowance of the ultimate lateral speeds is the smallest,and thereby the results provide the guidelines for choosing moon environment and initial conditions for implementing soft landing of the lander successfully.